I have a 24 valve so i am not up on the 12 valve talk but my buddy has a 97 with 370's pretty big delivery valves, M11 charger, 4K governor springs kit and some other minor mods. He wants to get this truck timed but he dosnt know what to advance it to. Somebody help me out so i can tell him thanks. He dynoed it last year and it was only at 414 horse with all of that and he has a dual disk clutch so it was putting the power to the ground. I know this truck is capable of more than that.